St. Ambrose: Faith and good works

"FAITH, then, has [the promise of] eternal life, for it is a good foundation. Good works, too, have the same, for an upright man is tested by his words and acts. For if a man is always busy talking and yet is slow to act, he shows by his acts how worthless his knowledge is: besides it is much worse to know what one ought to do, and yet not to do what one has learned should be done. On the other hand, to be active in good works and unfaithful at heart is as idle as though one wanted to raise a beautiful and lofty dome upon a bad foundation. The higher one builds, the greater is the fall; for without the protection of faith good works cannot stand. A treacherous anchorage in a harbour perforates a ship, and a sandy bottom quickly gives way and cannot bear the weight of the building placed upon it. There then will be found the fullness of reward, where the virtues are perfect, and where there is a reasonable agreement between words and acts."

~St. Ambrose: On the Duties of the Clergy, Bk. II, Chap. 2.

Altarpiece of St. Ambrose, by Alvise Vivarini.

Oil on panel, 1503; Santa Maria Gloriosa dei Frari, Venice.